Does connection between batteries and inverter require a fuse?

[yamsack]

Hi all,<br>I'm getting ready to finally wire up my solar components in the next week.&nbsp; For the solar panels and controller, I'll be using a 20 amp inline fuse with a 12 gauge wire.<br><br>Does the wiring from the batteries to the inverter require an inline fuse as well?&nbsp; If so, will 20 amps be sufficient?&nbsp; Secondly, should the fuse holder have 4 gauge wiring as well?&nbsp; Do they even make an inline fuse holder with 4 gauge wiring?&nbsp; Thanks all.<br><br><br>

 

[blars]

Yes, if your inverter does not have an internal fuse or breaker it is a good safety idea to use one.&nbsp; I got a fuse holder and two maxi-fuses (40 and 80 amp) for about $12 at walmart, it can handle 4awg wire.&nbsp; It's marketed for car audio.&nbsp; The fuse size depends on the size of the inverter, 20 amps would be about the right size for a 200 watt inverter.<br><br><br><br>

 

[SoulRaven]

I don't run a fuse because as said there is a fuse in mine, the bigger worry is the Gage of wire... Just be sure the inverter when ya buy it is a quality brand and has the needed fuse...<br>

 

[yamsack]

My pure sine inverter is 600 watts.&nbsp; It's made by Power Bright and is a quality inverter, so there's most likely fuse protection built in the inverter.&nbsp; <br><br>If I do install a fuse, I'm guessing that I will need a 60 amp inline fuse?<br>

 

[blars]

Properly crimped connections are more reliable than soldered in a high-vibration enviornment.<br>

 

[VanTramp]

My pure sine inverter is 600 watts.&nbsp; It's made by Power Bright and is a quality inverter, so there's most likely fuse protection built in the inverter.&nbsp; <br><br>If I do install a fuse, I'm guessing that I will need a 60 amp inline fuse?<br>

<div><br></div><div>You absolutely should install a fuse for the reasons 4x4 mentioned. &nbsp;I have a 150 Amp inline breaker I installed as close as I could to the positive cable of the battery. Consider that if anything between the inverter and the battery penetrated the cable and was in any way grounded to the chassis, perhaps due to routing through a firewall etc, you have a short circuit and potentially a fire and your fuse equipped inverter wouldn't have any control over it. The fuse in the inverter is for overload protection which is a much different scenario. &nbsp;Size the fuse based on the cable/run length and make sure it is high enough the inverter draw won't blow it. The overload fuse in the inverter handles that condition. The inline fuse protects the van and wiring etc. You want it large enough that the inverter can get all the power it wants without tripping it and with the least additional resistance.&nbsp;</div><div><br></div><div>I am planning to switch out my breaker to a 300Amp T type fuse. My system is wired with 2/0 welding cable and the inverter is in excess of 3000 watts peak. When I run the toaster oven, it puts a 106 - 112 amp load on the bank. That is at a max of 1850 watts. I don't want to limit the inverter by staying with a breaker that is smaller than the inverter can draw.&nbsp;</div><div><br></div><div>The sizes I used for my system were based on Xantrex installation manual and the cable run length for my equipment.&nbsp;</div><div><br></div><div>Plenty of people go without, but I don't recommend it. I would never compromise safety to save a few bucks. My .02&nbsp;</div>

 

[yamsack]

@ 4x4tour,<br><br>"...How far is your inverter from the battery? "<br><br>My inverter will only be about 1-2 feet from the batteries.&nbsp; I think I'll go with 4 gauge wire (with a 60amp inline fuse directly connected to the battery).<br><br>Regarding the fuse between the controller and the batteries, should that fuse be also as close to the batteries as possible, or should that fuse be closer towards the solar controller?<br><br>

 

[Kisatchieman]

<P>I looked at my Coleman modified sine wave inverter,&nbsp;that my son gave me for Christmas 3 years ago and saw that it came equipped with 8 gauge power cables. The unit is a 800 watt, peak 1600 watt model. The cables are 3' in length. Seems like the cables should be larger, say 4 gauge according to 4x4tour's chart. The internal fuse for the inverter is 35 amp.</P>

 

[Sailrich]

<P>I have been learning a lot from you guys here. Thank you. I have a 1990 Ford F150 Van. Have started wirieing for 2 each 110 V outlets&nbsp;with 30 amp cord to&nbsp;outside electrical box then pigtail to outside source. I purchaced a battery cut off switch from Harbor Freight. mounted it to the fire wall. Plan to run 6 guage wire. from start battery to cut off switch 4 ft,&nbsp;then (as yet purchased 85&nbsp;Ah battery) then to&nbsp;60 A&nbsp;in line fuse 4 to 6 in. From there through Firewall to 800W cobra inverter, about 4 ft. &nbsp; Any input would be greatly appreciated. corrections and or suggestions.&nbsp; Happy Travels!</P>

 

[Seraphim]

Good thread. Thanks

 

[Waterpog]

ANY wire running from ANY power SOURCE needs to be fused.&nbsp;<div><br></div><div>That means a wire running from the battery, alternator, or house batteries needs to be fused. For wires running from one source to the other it should be fused ad BOTH ends, often this is done with a disable link wire rather than a replacable fuse. The reason for this is to prevent fires in the case of a chafed or pinched wire.&nbsp;</div>

 

[slakrboy]

Always always ALWAYS install a fuse as close as you can to any wires coming of the positive terminal of a battery.&nbsp; All it takes is for a crimp connection to come off while you are moving and the wire touching the frame, and you are on the side of the road with your trailer/car on fire.

 

[Wrxdwnshft]

I don't run a fuse because as said there is a fuse in mine, the bigger worry is the Gage of wire... Just be sure the inverter when ya buy it is a quality brand and has the needed fuse...<br>

You understand that the fuse isn't entirely to save your equipment but to protect the wire from arching and burning up in turn that will save your rig. If you have no fuse the fuse will blow on your unit but will leave the wires connected to the batteries live and dangerous.

 

[Weight]

This is an old thread reborn. Fuses protect wires. There must be a fuse at the battery positive. There must be a fuse at the battery positive. The internal fuse in whatever device will not protect the cable from starting fire during a short. There must be a fuse at the battery positive.

 

[1shemp]

If you use a smaller wire on the hot side it will serve as a fuse.

 

[B and C]

^^^ I won't ask you to help me with any electrical work.

An undersized wire for the load can cause a fire and if no fire possible damage to the inverter when it is asked to produce more than the skinny wire can supply. No substitute for a properly sized wire and fuse.

 

[SmilinEd]

^^^ I won't ask you to help me with any electrical work.

An undersized wire for the load can cause a fire and if no fire possible damage to the inverter when it is asked to produce more than the skinny wire can supply.  No substitute for a properly sized wire and fuse.

Good thread ppl... :thumbsup:

 

[crofter]

Properly crimped connections are more reliable than soldered in a high-vibration enviornment.<br>

Do you need to tinn the stranded wire before crimping on the connector?
-crofter

 

[Weight]

Crimped wire terminals do not require tinning. I would use shinny copper wire, not old oxidized. Be sure the terminals are tinned copper, many cheap ones are aluminum. A bit of No-Ox would help with bare wire. If using marine grade, it is already tinned. Wire and stuff= https://www.genuinedealz.com/

How to crimp wires= https://marinehowto.com/marine-wire-termination/ Even big wires= https://marinehowto.com/making-your-own-battery-cables/

 

[Spaceman Spiff]

Do you need to tinn the stranded wire before crimping on the connector?
-crofter

Soldering or tinning a wire without proper cool down (annealing) leaves the wire less flexible and more prone to fracture.

Crimping is preferred in high vibration environments.